41 L.Ed.2d 535 94 S.Ct. 2757 418 U.S. 1 COMMISSIONER OF INTERNAL REVENUE, Petitioner,v.IDAHO POWER COMPANY. No. 73?263. Argued Feb. 27, 1974. Decided June 24, 1974. Syllabus Section 167(a) of the Internal Revenue Code of 1954 allows a depreciation deduction from gross income for ‘property used in the (taxpayer’s) trade or business’ or ‘held for […]